Well, the first week I was on Amitiza I had diarrhea and cramping. Then for a week and a half I was terribly constipated. Now, for the past 3 days or so I have had a lot of bloating, frequent soft (but not diarrhea) stools that are, I'm sorry to say, pretty smelly plus smelly gas! I've had lots of rumblings and "popping gas" that I can hear in my gut. My stool has been kind of greenish lately too. No idea why. I'm just glad I can "go"...but that bloating makes me look odd because my gut doesn't match the rest of me. You would think that if I am pooping normally my gut would be flat, but it isn't, and I suspect it has to do with the Amitiza.
Every day is a new adventure in my IBS world.